A new study powered by Northern Arizona University's FEWSION Project found the water crisis in the Rio Grande basin is severe—potentially just two dry winters away from a major water shortage for farms and communities in New Mexico, Texas and Mexico.
The study, published Nov. 20 in Discover Water , was led by Brian Richter of Sustainable Waters and included Kat Fowler, a Ph.D. student in informatics and computing, and Ben Ruddell, a professor in the School of Informatics, Computing, and Cyber Security at NAU and creator and director of FEWSION, which maps the vulnerabilities, environmental footprints and resilience of U.S. supply chains. This is the partnership's third study looking at dwindling water supplies along major U.S. river basins.
The researchers found that the overconsumption of water was primarily due to irrigated agriculture, and of that, the largest factor was cattle-feed crops such as alfalfa and grass hay. Only about half of the water being used is being replaced by natural processes. Already, surface water has dried up in June where the growing season lasts through October.
"This severe water crisis presents an opportunity for envisioning a more secure and sustainable water future for the basin, but a swift transition will be needed to avoid damaging consequences for farms, cities and ecosystems," the researchers wrote.
In addition to the effects on humans—the Rio Grande and underlying aquifers provide drinking water for more than 11 million people in Mexico and 4 million people in the United States—natural ecosystems are at risk. The Rio Grande basin supports more than 130 mammals, 3,000 plant species and 500 bird species, and the wetlands are critically important to migratory birds. Already at least 75 freshwater fish species are at risk as their ecosystems disappear with the water.
These are the same trends the researchers noted when looking at the Colorado River basin and Great Salt Lake , both of which play significant roles in western ecosystems and economies.
"In most parts of the western United States, as in other mountainous and desert regions worldwide, the problem is the same: We are using more water in most years than nature makes available, and there is a growing shortage," Ruddell said. "In the Rio Grande, there is an added problem, which is that the river is shared by two nations, and one of the nations—Mexico—is using more water than it has a right to. That creates a big problem for downstream farmers in Texas."
Reversing this process will take intentional action, Ruddell said. One solution the researchers proposed is implementing "rotational fallowing" programs, which pay farmers to reduce water use before reservoirs or groundwater runs dry. The region also needs significant investments in water infrastructure to add new supply, efficiency and storage.
